API-103. Update to metrics 3.1.2
API-103. Update to metrics 3.1.2

Change-Id: Ic7c50adbad192be1965a062eebdd9944188e5d53
Reviewed-on: https://review.streamsets.net/8028
Reviewed-by: Jarcec Cecho <df2d427dacaa504f2ede0aed47c4cdf043778b95@streamsets.com>

streamsets/datacollector-api,streamsets/datacollector-api